The final volume of the trilogy brings to a fitting end the saga of the Lon Tobyn Chronicle. While the first volume took place primarily in Tobyn-Ser and in Lon-Ser for the second installment, Coe switches between both lands here in just about equal measure. In Lon-Ser, we follow the trials and tribulations of Melyor, the sovereign of Bragor-Nal while Tobyn-Ser prepares for war. The title Eagle-Sage refers to the bonding of an eagle to a mage-- something that only happens when war comes to Tobyn-Ser and has only happened three times in its 1000 year history. Uniquely, this time two mages bond to eagles-- Jaryd (our 'golden boy' from the first volume) and Cailin, the youngest mage ever. The problem is who or what the 'bad guys' are. Is there to be a civil war in Tobyn-Ser, perhaps between the two rival sects of mages? Or is the threat external, as it always was in the past...
Overall, this is an interesting trilogy to be sure and Coe tells a pretty good tale. I really liked the different cultures existing in Lon and Tobyn-Ser-- one a 'classic' fantasy setting and one industrialized/modern to a degree. You have to suspend some disbelief that such a juxtaposition could exist for as long as it has (1000 years!) and that the two societies had little to no contact with one another, but so be it. Coe creates not just one world here, but two, both fleshed out in detail (after all, each volume was a door stop of over 600 pages).
In a way, the trilogy features a classic redemption tale of overcoming various adversities by various protagonists in both Tobyn and Lon-Ser. The final volume features as well a classic good versus evil motif, with an evil 'unbound' spirit mage assuming human form once again (like a possession) in a live human mage intent on taking revenge and the various sects of mages coming together finally to stop him; Coe gives us a neat denouement here, although one not entirely unexpected.
The strengths of the series reside in the detailed characters, intricate plotting and world building; the primary weaknesses I feel are the numerous info dumps and the at times tedious retelling of events from various POVs. If you are a Sanderson fan, I think this series will appeal. If you like your fantasy darker, maybe not. All in all, 3.5 for this volume and the series as a whole.